What is anxiety? Ask anyone to define anxiety and you will quickly realize there is no shortage of examples that people can provide. Although anxiety is a very common human experience, the descriptions that people provide are quite varied.

Anxiety is a human emotion. Everyone experience it. Yet, each person experiences this emotion in unique ways. The following case examples illustrate these various experiences of anxiety:

Sally is a 24-year-old sales associate in a highly prestigious pharmaceutical firm. She constantly works under a great deal of pressure. She says it's "no big deal." She even believes she thrives off this stress. However, she recently walked into her local grocery store and began to sweat. Her heart began to race. She felt like she was losing control. This happened on several occasions. She became so distressed she decided to order her groceries online to avoid another repeat episode.

Bill is a 47-year-old hardware store owner. Bill is constantly "worrying" about (what seems to him) just about everything. Whether he is concerned about his business not doing well…or, what if that mole on his back is not just a beauty mark?...or, how on earth is he ever going to drive to Michigan all by himself to see his son (even with the brand new navigation system)?…Bill just cannot seem to "control" his worry.

Kim is a 36-year-old, part-time, freelance web-designer. She is ordinarily calm and low-key. This is true until she has to go over a bridge, or travel in an airplane. For Kim, she hates places where she feels she cannot escape. She finds that she will often worry for days or even months in advance of these situations. As a result, she makes it a habit to avoid these situations at all costs; or, she "barely gets through them."

Lastly, we have Pete. He is a 32-year-old law student. Pete cannot quite explain why he is anxious; however, he wakes up every morning feeling a sense of "dread." His anxiety usually lingers until about mid-day. At that point, he finally gets into the swing of his normal, daily routine.

So who is right? Are they all describing the same thing? Simply stated, yes they are. The reason behind this paradox is that anxiety is best considered a complex, subjective experience. Anxiety is produced by multiple causes. It is expressed by a diverse set of symptoms. These symptoms include physical, emotional, behavioral, and cognitive components. This is why we can ask many different people about a very common experience; yet, get totally different definitions of what it means to be anxious.

People also differ in how often, and how intensely, they experience anxiety. For most people, anxiety is a normal and even adaptive occurrence. A normal degree of anxiety is part of the everyday human experience. Unfortunately, other people may experience anxiety to such a heightened degree that it causes them great distress. Sadly, this level of anxiety can interfere with people's ability to function well. It may affect many important areas of their lives such as work, school, and relationships. When anxiety reaches this level of distress, and results in impaired functioning, we begin to speak of an anxiety disorder.

Luckily, experts in the field have come a long way in understanding and treating anxiety problems. In the following article, we examine the many facets of anxiety. We will begin with a more in-depth understanding of both the beneficial and harmful aspects of anxiety. Next, we'll talk about what happens when anxiety becomes "pathological" or disordered. We describe and explain the many different types of anxiety disorders. We will present relevant research about what experts believe are the reasons behind the development, and maintenance of anxiety disorders. This same body of research has developed highly effective treatments for the different types of anxiety disorders. With this information, we confidently conclude there is hope and relief for the millions of people who struggle with anxiety.